A bio-inspired suction cup actuated by shape memory alloy(SMA)for miniature wall climbing robots is developed based on studying characteristics of biological suction apparatus.Some fast control strategies are introduc...A bio-inspired suction cup actuated by shape memory alloy(SMA)for miniature wall climbing robots is developed based on studying characteristics of biological suction apparatus.Some fast control strategies are introduced to improve negative pressure response.Theoretic model of the suction cup is built,and simulation and experiments results indicate the effectiveness of the fast control strategies.The largest negative pressure of the suction cup can reach 14 000 Pa,and its generating and cancelling just need 5 s.Research results indicate the suction cup can be used as an adhesion mechanism for miniature wall climbing robots.展开更多
Efforts have increased to measure nitrate losses from farmland under different management practices due to environmental and public concerns over levels of nitrate-nitrogen (NO<sub>3</sub>-N) in surface an...Efforts have increased to measure nitrate losses from farmland under different management practices due to environmental and public concerns over levels of nitrate-nitrogen (NO<sub>3</sub>-N) in surface and ground waters. This study evaluated the effect of conventional tillage (CT) and strip tillage (ST) practices and three N application rates on NO3-N concentrations in soil water at a 76 cm depth under irrigated sugarbeet (Beta vulgaris L.) in a clay loam soil. Nitrogen rates were applied as dry urea at 120, 150, 180 kg N ha-1</sup> in 2006;130, 160, 190 kg N ha-1 in 2007;and 110, 140, 170 kg N ha<sup>-1</sup> in 2008. Soil water volumes were measured weekly during each growing season using three ceramic suction cup samplers per plot placed at a 76 cm depth below the soil surface under each tillage. Results indicated that NO<sub>3</sub>-N concentrations at the 76 cm depth in the soil profile were not significantly affected by either tillage practice or by N application rate due to soil variability across the field and due to suction cup samplers’ biased estimate of soil water. The three N rates under CT and ST practices maintained NO<sub>3</sub>-N concentrations below the root zone to levels exceeding the 10 mg L<sup>-1</sup> safe drinking water maximum level in all three years. There were large variations in NO<sub>3</sub>-N concentrations among replicates within each tillage and N rate that were likely caused by variability in soil physical, hydraulic and chemical properties that impacted water movement through the soil profile, N dynamics and leaching below the root zone of sugarbeet. In conclusion, suction cup samplers are point water measurement devices that reveal considerable variability among replicates within each treatment due to the heterogeneity of field soils. Further, these samplers are not recommended in heterogeneous soils with preferential flow characteristics.展开更多
Congenital skull fractures of newborn are rare and create medico-legal problems. Their management is controversial. Between surgery considered too aggressive and uncertain conservative attitude, reduction by suction c...Congenital skull fractures of newborn are rare and create medico-legal problems. Their management is controversial. Between surgery considered too aggressive and uncertain conservative attitude, reduction by suction cup or breast pump is an alternative. The authors report their experience through a case of successful resolution of a congenital depressed skull fracture using a suction cup in a newborn at 13 day of life followed by a literature review. This technique avoids the usual complications of surgery and reduces the anxiety of parents related to surgery. It also avoids the anxiety of having a newborn with a recessed skull and a conservative attitude with uncertain outcome.展开更多
Existing robotic end-effector gripping technologies often encounter challenges such as poor adaptability to environmental changes,incomplete deformation sensing,and insufficient adhesion stability,which can compromise...Existing robotic end-effector gripping technologies often encounter challenges such as poor adaptability to environmental changes,incomplete deformation sensing,and insufficient adhesion stability,which can compromise operational safety and reliability.Here,we present the bio-inspired self-sensing suction cup,in which the core self-sensing capability is achieved by combining high-performance,laser-induced graphene/Ag NWs flexible sensors with a Wheatstone bridge design.The flexible sensors provide high sensitivity,while the Wheatstone bridge circuit enables accurate and stable detection of deformation during the gripping process.Integrated into the octopus-inspired suction cup,this system allows for real-time monitoring of deformation and adsorption stability.The self-sensing suction cup demonstrates good performance across a 0–25 kPa negative pressure range,with outstanding linearity(R^(2)=0.993)and high sensitivity(GF=10.436 kPa^(−1)).Experimental results confirm that the suction cup can achieve stable adsorption under varying loads and enable real-time monitoring of the suction cup status during the gripping process.This design provides a promising solution for intelligent gripping systems,logistics,and object recognition in challenging environments.展开更多
基金National Science and Technology Foundations of China(No.61075086,No.60875058)the Hi-Tech Research and Development Programof China(863 Program)(No.2009AA04Z221)
文摘A bio-inspired suction cup actuated by shape memory alloy(SMA)for miniature wall climbing robots is developed based on studying characteristics of biological suction apparatus.Some fast control strategies are introduced to improve negative pressure response.Theoretic model of the suction cup is built,and simulation and experiments results indicate the effectiveness of the fast control strategies.The largest negative pressure of the suction cup can reach 14 000 Pa,and its generating and cancelling just need 5 s.Research results indicate the suction cup can be used as an adhesion mechanism for miniature wall climbing robots.
文摘Efforts have increased to measure nitrate losses from farmland under different management practices due to environmental and public concerns over levels of nitrate-nitrogen (NO<sub>3</sub>-N) in surface and ground waters. This study evaluated the effect of conventional tillage (CT) and strip tillage (ST) practices and three N application rates on NO3-N concentrations in soil water at a 76 cm depth under irrigated sugarbeet (Beta vulgaris L.) in a clay loam soil. Nitrogen rates were applied as dry urea at 120, 150, 180 kg N ha-1</sup> in 2006;130, 160, 190 kg N ha-1 in 2007;and 110, 140, 170 kg N ha<sup>-1</sup> in 2008. Soil water volumes were measured weekly during each growing season using three ceramic suction cup samplers per plot placed at a 76 cm depth below the soil surface under each tillage. Results indicated that NO<sub>3</sub>-N concentrations at the 76 cm depth in the soil profile were not significantly affected by either tillage practice or by N application rate due to soil variability across the field and due to suction cup samplers’ biased estimate of soil water. The three N rates under CT and ST practices maintained NO<sub>3</sub>-N concentrations below the root zone to levels exceeding the 10 mg L<sup>-1</sup> safe drinking water maximum level in all three years. There were large variations in NO<sub>3</sub>-N concentrations among replicates within each tillage and N rate that were likely caused by variability in soil physical, hydraulic and chemical properties that impacted water movement through the soil profile, N dynamics and leaching below the root zone of sugarbeet. In conclusion, suction cup samplers are point water measurement devices that reveal considerable variability among replicates within each treatment due to the heterogeneity of field soils. Further, these samplers are not recommended in heterogeneous soils with preferential flow characteristics.
文摘Congenital skull fractures of newborn are rare and create medico-legal problems. Their management is controversial. Between surgery considered too aggressive and uncertain conservative attitude, reduction by suction cup or breast pump is an alternative. The authors report their experience through a case of successful resolution of a congenital depressed skull fracture using a suction cup in a newborn at 13 day of life followed by a literature review. This technique avoids the usual complications of surgery and reduces the anxiety of parents related to surgery. It also avoids the anxiety of having a newborn with a recessed skull and a conservative attitude with uncertain outcome.
基金supported by the National Natural Science Foundation of China(52205589)the Chongqing New Youth Innovation Talent Program(CSTB2024NSCQ-QCXMX0086)+5 种基金the National High-end Foreign Experts Introduction Plan(G2022035005L)the Natural Science Foundation of Chongqing Municipality(CSTB2024NSCQ-JQX0003)the Science and Technology Research Program of Chongqing Municipal Education Commission(KJZD-K202300606,KJZD-K202200609)the China Postdoctoral Science Foundation(2023T160765,2022MD713695)the Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)the Bayu Scholars Program。
文摘Existing robotic end-effector gripping technologies often encounter challenges such as poor adaptability to environmental changes,incomplete deformation sensing,and insufficient adhesion stability,which can compromise operational safety and reliability.Here,we present the bio-inspired self-sensing suction cup,in which the core self-sensing capability is achieved by combining high-performance,laser-induced graphene/Ag NWs flexible sensors with a Wheatstone bridge design.The flexible sensors provide high sensitivity,while the Wheatstone bridge circuit enables accurate and stable detection of deformation during the gripping process.Integrated into the octopus-inspired suction cup,this system allows for real-time monitoring of deformation and adsorption stability.The self-sensing suction cup demonstrates good performance across a 0–25 kPa negative pressure range,with outstanding linearity(R^(2)=0.993)and high sensitivity(GF=10.436 kPa^(−1)).Experimental results confirm that the suction cup can achieve stable adsorption under varying loads and enable real-time monitoring of the suction cup status during the gripping process.This design provides a promising solution for intelligent gripping systems,logistics,and object recognition in challenging environments.
